1. Field of the Invention
The present invention relates to a gas-powered auxiliary engine and universal mount assembly for a multi-wheeled vehicle, e.g., a bicycle. More particularly, the invention relates to an engine assembly which selectively, drivingly engages the rear wheel of a bicycle, is readily attached to and detached from almost any size and/or style of bicycle, and includes uncomplicated safety features.
2. Description of the Prior Art
The present invention provides an extremely light weight and uncomplicated auxiliary engine and universal mounting assembly therefor, so that the engine may be readily attached to most any type of bicycle or other multiwheel manually powered vehicle, with minimum difficulty. Furthermore, the instant invention provides: brake actuated kill switches for the engine, an important safety feature; a mounting assembly which spring urges the engine into a non-driving, fail safe configuration, another important safety feature; and a cable operated clutch arrangement which provides engagement of the engine drive wheel with the rear tire of the bicycle, unlike prior art auxiliary engine assemblies. A further safety feature may be a key operated engine kill switch associated with the bicycle seat, for example. The Dead Man switch assures that the engine is disabled automatically should the rider become separated from the bicycle. Additionally, the present invention provides a unique drive wheel made of polyurethane material or the like, the drive wheel providing a vibration reducing, cushioned mount for the engine when the drive wheel is engaged with the bicycle driven wheel, the assembly also serving as a vibration dampener to greatly reduce the effects of vibration not only from the engine but also from the terrain over which the bicycle is ridden; furthermore, the assembly has been found quite effective in maintaining a secure engagement of drive wheel and driven wheel even when the terrain over which the bicycle is ridden is very rough, or even of washboard configuration.
It is well known in the prior art to equip an existing pedal powered bicycle with an auxiliary engine. However, a number of distinct disadvantages are encountered with prior art motorized bicycles. Some examples are: mounting of the engine requires substantial modification to the conventional bicycle; the installation of prior art auxiliary engines is time-consuming and expensive for the average novice mechanic; and such assemblies often require an engine of special design, an unnecessary additional expense.
The prior art of motorized bicycles discloses the practice of having a drive arrangement that includes a motor driven friction pulley, such as a friction wheel, or the like, which drive arrangement contacts the surface of a rear tire of a bicycle. Further, such prior art discloses the practice of a spring biasing the auxiliary engine so as to maintain driving contact between the friction device and the bicycle tire. Further, prior art motorized bicycle assemblies generate considerable difficulties in their installation onto existing bicycles, especially in view of their complicated driving arrangements. These installations necessitate extensive modification to the bicycles onto which they are to be mounted.
Examples of prior art auxiliary engine assemblies for conventional, pedal driven bicycles will now be discussed in some detail.
U.S. Pat. No. 1,158,311, issued Oct. 26, 1915 to George S. Schunk, shows an auxiliary engine for bicycles, pivotally mounted behind the bicycle seat, but requiring a spring arrangement to force the engine drive wheel onto the rear tire of the bicycle. No provision whatsoever is made to readily and easily remove the engine drive wheel from the bicycle rear tire.
U.S. Pat. No. 2,491,076, issued Dec. 13, 1949 to Mario Benazzoli, discloses an auxiliary engine for a bicycle including an engine spring slung mounted beneath the pedal cranks and no provision is made for displacing the drive roller or wheel of the engine from the bicycle rear tire.
Schunk and Benazzoli exemplify prior art attempts which fail to keep an auxiliary engine drive wheel off of the rear tire.
U.S. Pat. No. 2,586,082, issued Feb. 19, 1952 to Sanzio P. V. Piatti, discloses an auxiliary engine with a drive wheel, spring urged into engagement with a bicycle wheel, rather than away from the bicycle wheel. A cable and hand control are employed to move the engine and roller away from the driven bicycle wheel, not toward it as in the instant invention. Thus, there is no shock absorbing action for the engine when disengaged, since there is no spring support for the engine in this attitude, again unlike the present invention. Furthermore, should the cable support system of Piatti fail, then the engine and drive wheel will fall onto the bicycle wheel, thus creating a potentially very unsafe situation. Additionally, Piatti addresses the problem of heat transfer and admits the problem of the tire becoming overheated. However, the solution taught in Piatti is to provide an engine drive wheel with an internal cooling fan, which is completely inapposite to the instant invention, where an engine carriage also functioning as a heat sink reduces heat transfer to the drive wheel to an acceptable minimum.
U.S. Pat. No. 3,339,659, issued Sep. 5, 1967 to Walter A. Wolf, discloses two auxiliary engine powered cones which are frictionally engaged with a bicycle tire 80, by reason of both the weight of the power unit plus the forces exerted by a pair of tension springs, urging the cones into firm engagement with the bicycle rear tire 122. As pointed out in this patent (column 1, lines 16 to 29) considerable difficulty has been encountered in the prior art in maintaining a uniform and efficient driving engagement of the auxiliary engine drive wheel to the bicycle tire; the problem is solved by use of the present invention, without need of complex drive wheels and spring assemblies, as will be detailed below.
U.S. Pat. No. 3,966,007, issued Jun. 29, 1976 to Ralph L. Havener, et al., discloses an auxiliary electric motor for a bicycle with a battery and battery casing disposed between the rider's legs. Both weight and location of components proposed by Havener, et al., generate obvious problems.
U.S. Pat. No. 4,200,164, issued Apr. 29, 1980 to Frank S. Pearne, represents an improvement over the art as just discussed, disclosing an auxiliary engine for a bicycle which is readily mounted onto and detached from the bicycle. However, the Pearne arrangement requires an extra handle for operating the engine and, similarly to the art set forth above, requires a tension spring arrangement to urge the engine drive wheel onto the bicycle rear tire, in direct contradistinction to the present invention, which utilizes spring force to urge the drive wheel away from the tire. Again, and as is the case with other prior art discussed above, the proposed arrangement likely will not keep the drive wheel in engagement when the bicycle is ridden over rough terrain of any kind, and Pearne completely fails to address the matter of heat transfer problems.
In summary, the art exemplifies prior attempts to provide an adequate auxiliary engine for a bicycle, all of which fail to force an auxiliary engine drive wheel off of the rear tire, rather than onto it, and provide selective engagement of the engine drive wheel with a bicycle tire, without need of utilizing anything other than a cable tension assembly and the force of gravity.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.